It's good for chess fans, for Magnus Carlsen, for his competitors to realize that as great as the world champion is, he's not invincible. Not only can he be defeated (sometimes) in individual games and in round-robin tournaments (sometimes), he can be defeated in matches, too. Case in point: the finale of the Skilling Open. Carlsen defeated Ian Nepomniachtchi in one semifinal while Wesley So defeated Hikaru Nakamura in the other (I may write a later report on that round and on the quarterfinals as well, as there were many interesting games in those rounds), setting up what turned out to be an epic final.
For those who didn't watch the event, the way it worked was this: matches took two days and consisted of a pair of four-game mini-matches. If each player won one of the mini-matches or if both were drawn, then there would be a two-game blitz playoff followed if necessary by an Armageddon game. While they didn't reach the Armageddon stage (though a couple of the earlier matches did), it made it all the way to the blitz playoff.
On day 1, all four games were decisive, with White winning all the games. Carlsen struck first, and So came back twice to level the scores and ultimately draw the first mini-match. Both players made errors in all four games, but the result of every game was the most logical one.
On day 2, Carlsen again struck first with a win in game 1, but this time with Black. Normally, that would be that, but not this time, as So promptly returned the favor, outplaying Carlsen convincingly in his black game. The third game was the first draw of the match, albeit one where both players had an opportunity to win. (So's winning chance came first, but it required a deep and beautiful tactical idea that was probably almost impossible for a human to find in a short time control game, though any strong GMs reading this are welcome to correct me if I'm underestimating their tactical prowess. Adding to the degree of difficulty was the tension and the fact that this was the ninth consecutive day the players were in action.) The last game of the mini-match was a non-game, with Carlsen allowing So to make a short, easy draw in a well-known line of the Berlin.
To the tiebreaks. Carlsen looked punch-drunk in the first game, simply blundering with 15...c5 and compounding his problems with 17...Ra5. He made a good fight of it, and a series of So errors brought Carlsen to within range of a draw - only to make another tactical error with 37...d4. This time it proved fatal, and So took the lead for the first time in the match. In the second game, So was very comfortable most of the way - but there was one significant exception. So showed that he too was tired and capable of slips by this point in the match, blundering a pawn with his 17th move. A few loose moves by Carlsen allowed So to not only equalize but even take over, and the American could have played for (and probably achieved) a win had there been any need to. Instead, he forced mass exchanges to ensure the draw, and with it a hard-earned victory.
We'll see if this is just a little bump in the road for Carlsen before he goes on to win another ten or so tournaments in a row, or if the peleton is finally reeling him in. In the meantime, congratulations to Wesley So!
The games, with my notes, are here.